Blue Orchard Mason Bees and Their Condo in Kensington Park

Blue bees were a great surprise to me when I first discovered them. I had always thought of bees as yellow, orange, and black insects until that moment. It was lovely to see the beautiful flashes of metallic blue created by blue orchard mason bees as they explored flowers.

The city where I live is currently encouraging people to care for bee condos designed to house the mason bee, which is a very helpful pollinator. A “bee condo” is an artificial structure that provides a suitable place for bees to lay their eggs. There’s a condo in a park near my home. Pollinators are facing a range of problems today and need our support.

Blue orchard mason bee; photo by Robert Webster, CC BY SA 4.0 license

The Blue Orchard Mason Bee

The blue orchard mason bee has the scientific name Osmia lignaria. The scientific name is useful to identify the bee when it’s being discussed. Since the common name of the insect is quite a mouthful, it’s often abbreviated. The insect is sometimes called the blue orchard bee, for example.

The insect is found in both Canada and the United States. Mason bees are solitary insects that get their name from the nest that they build for themselves. They use mud, clay, or grit to build the nest. They are also known as orchard bees because they are excellent pollinators of fruit trees. According to the University of Florida, Osmia lignaria is also valued for pollinating blueberry bushes.

Blue orchard mason bees are solitary insects and don’t live in a hive. They don’t produce beeswax or honey, either. They are capable of stinging but rarely do. They carry pollen on the underside of their body instead of on their legs.

The females create their nest in tubular cavities that they find, such as a hole in a tree trunk, a crack in a stone, or even a piece of a hose or a section of a pipe. Although the animals are solitary, in a bee condo they readily build their nest in an individual compartment surrounded by the compartments of other bees.

A magnified view of the back of Osmia lignaria; photo from USDA, public domain license

Life Cycle

The insect’s life cycle begins with the emergence of the new females and males from their cocoons. A male mates with a female and soon dies. The female then looks for a roughly tubular cavity in which she can lay her eggs.

Once she’s found a good spot to create her nest, the female builds a layer of mud at the back of the tube. She then collects pollen and nectar, which she deposits on top of the mud layer. She presses the materials into a ball to support the egg that she lays. The ball provides food for the developing bee. The female seals the egg in the cavity with a mud wall while leaving space for the larva to develop. The wall acts as the back of the next chamber. The bee then repeats the process, laying one egg after another in a chain of chambers. The final egg is sealed in the nest with a thick covering of mud.

The females die before the winter arrives. The eggs develop into larvae and eventually adults within the chambers. In the following spring, the new adults break through the mud wall that covers them and emerge from the nest. The cycle then continues.

Researchers have discovered that the eggs in the back part of the nest produce females and the ones in the front produce males. This allows the males to emerge first in the spring and to be ready to mate with a female as soon as she appears. It has been suggested that it’s also a protective mechanism for the population. If a predator attacks the nest, they will reach the males first and may not get to the females. Although some males are needed for fertilization, the females are more important to the population because they lay the eggs that produce the next generation.

Blue orchard mason bee larvae in their chambers; photo by USDA, public domain license

The Importance of Pollinators

The USDA (United States Department of Agriculture) says that “three-fourths of the world’s flowering plants and about 35 percent of the world’s food crops depend on animal pollinators to reproduce”. Bees are by far the most common of the animal pollinators in the world.

According to the USDA, while honeybees are very important for pollinating commercial crops in North America, native bees such as the blue orchard mason bee are better for pollinating our native plants. (Honeybees are not native to the continent.) Blue orchard mason bees are bred in captivity and sold to farmers for their pollination abilities.

A bee condo in Kensington Park

Kensington Park and Its Bee Condo

Kensington Park is an enjoyable place for the people in my area to visit. It offers multiple attractions, including a pitch and putt golf course, an ice skating rink, an outdoor swimming pool, tennis courts, a running track, and a children’s play area.

My favourite part of the park is the large area of grass to the north of the facilities. This contains scattered picnic tables and trees as well as a section containing cultivated plant beds. This section is located near a main road and is where the bee condo has been erected. The traffic doesn’t seem to deter the bees. Commercial fruit growers may create similar structures in their orchards in order to house their bees. The structures can also be bought in some stores or can be handmade.

A close-up view of the bee condo

The “condo” is a box filled with tubes placed at the top of a tall pole. Similar condos are found in other parks in the area as well and seem to be successful. At the start of winter, the tubes are removed and cleaned. They contain cocoons, each of which contains an adult bee. The adults don’t emerge from the cocoons until the spring, however. The cocoons are removed from the tubes and stored until spring begins. The cleaned tubes are eventually returned to the box that acts as their enclosure.

I took the photos of the condo in this article, but I had to use other people’s photos of the bees. I do have my own photos, but they are too blurred to use. I’m determined to get a good photograph of the insects this summer, assuming the bees appear again. I very much hope that they do, not only for my sake but also for the sake of the plants that they pollinate.